ObjectiveTo observe alterations of macular outer retinal reflectivity (ORR) and the associations with macular vessel density in patients with nonproliferative diabetic retinopathy (NPDR). Methods A retrospective cross-sectional study. From August 2021 to March 2022, a total of 63 NPDR patients with 63 eyes (NPDR group) diagnosed by Department of Ophthalmology of Guangdong Provincial People's Hospital were included in the study. There were 39 males with 39 eyes and 24 females with 24 eyes. Age was 60 (52, 68) years. A total of 66 eyes of 66 healthy volunteers matching age and sex were selected as the control group. Among them, 40 men had 40 eyes and 26 women had 26 eyes. Age was 58 (52, 67) years. Optical coherence tomography (OCT) and OCT angiography (OCTA) were performed in all affected eyes. Image J software was used to calculate ORR, including the optical density of ellipsoid zone (EZ), photoreceptor outer segment (OS), photoreceptor inner segment (IS) and outer nuclear layer (ONL) by OCT examination. The sampling sites were horizontal and vertical scanning of the fovea of the macula on 500 μm (nasal500, temporal500, superior500, inferior500), 1 000 μm (nasal1 000, temporal1 000, superior1 000, inferior1 000) and 2 000 μm (nasal2 000, temporal2 000, superior2 000, inferior2 000). The software automatically divided the retina within 6 mm of the macular fovea into the fovea with a diameter of 1 mm, the parafovea with a diameter of 1-3 mm, and the perifovea with a diameter of 3-6 mm by macular OCTA examination. The blood density of superficial capillary plexus and deep capillary plexus in different zones in the macular area were measured by the built-in software of the device. Spearman correlation analysis was used to analyze the correlation between ORR and blood flow density. ResultsCompared with the control group, retinal reflectivity of EZ in NPDR group was significantly decreased at other sites except the fovea, retinal reflectivity of OS was significantly decreased at nasal2 000, temporal2 000, superior2 000 and superior1 000; retinal reflectivity of IS was significantly decreased at superior1 000, superior500 and inferior500. The retinal reflectivity of ONL in macular fovea was significantly decreased, and the differences were statistically significant (P＜0.05). The ORR was positively correlated with blood flow density, and the correlation coefficient in NPDR group was lower than that in control group. The results of multifactor linear regression analysis showed that the superior and temporal ORR were correlated with blood flow density (P＜0.05). ConclusionsCompared with the control group, ORR is reduced and less correlated with vessel density in NPDR patients. ORR is more affected by retinal blood flow density in temporal and superior parts.
Optic nerve diseases seriously affect visual function, and early accurate diagnosis and effective follow-up are very important for treatment and prognosis. Optical coherence tomography (OCT) and OCT angiography (OCTA) are non-invasive and high-resolution imaging techniques, which play increasingly important roles in the diagnosis and treatment of optic nerve diseases. OCT can visually display the structure of retinal nerve fiber layer and macular area, accurately measure the thickness of nerve fiber layer and structural parameters of macular area. OCTA can clearly display the changes of microblood flow around optic disc and retinal blood vessels. The combined use of these two technologies will not only help diagnose and monitor optic nerve diseases, but also deepen our understanding of the pathogenesis of optic nerve diseases. In view of the fact that the application of OCT and OCTA in neuro-ophthalmic diseases involving the optic nerve is still in the development stage in the domestic medical community, it is urgent to formulate a guiding document to regulate and promote the application of these two technologies. To this end, based on a systematic literature review and combined with the current clinical practice of OCT and OCTA in China, we formulated the Expert consensus on the clinical application of optical coherence tomography and angiography in optic nerve diseases. This consensus comprehensively expounds the technical principles and main measurement indicators of OCT and OCTA, the specific application, examination specifications and limitations of OCT and OCTA in clinical diagnosis and follow-up of neuroophthalmic diseases involving optic nerve, aiming to improve the application level of OCT and OCTA by doctors, especially neuroophthalmologists, and better play the role of this advanced imaging technology in neuroophthalmology.
ObjectiveTo observe the clinical and multimodal imaging features of eyes with acute macular neuroretinopathy (AMN) associated with the coronavirus disease 2019 (COVID-19). MethodsA retrospective study. From December 20, 2022 to January 17, 2023, a total of 29 patients (58 eyes) with COVID-19-associated AMN admitted to Department of Ophthalmology of Eye and ENT Hospital, Shanghai Medical College were included in the study. All the affected eyes underwent the best corrected visual acuity, color fundus photography, infrared fundus photography (IR), short-wavelength autofluorescence (SW-AF), near-infrared autofluorescence (NIL-AF), optical coherence tomography (OCT), and OCT angiography (OCTA). All patients were administered microcirculation-improving oral medication with 12 cases receiving adjunctive low-dose corticosteroid therapy. Follow-ups were conducted 1 to 3 months after the initial diagnosis, with a total of 19 cases (38 eyes) completing the one-month follow-up. ResultsOut of the 29 cases, there were 9 males (18 eyes) and 20 females (40 eyes), all of whom experienced bilateral eye involvement. The age of the patients ranged from 12 to 47 years, with an average age of (29.9±9.5) years. The time from the onset of fever to the appearance of ocular symptoms was (2.52±2.01) days. Among the 58 affected eyes, there were 5 cases with retinal cotton wool spots, 2 cases with optic disc edema, and 1 case with parafoveal branch retinal vein occlusion. All affected eyes exhibited deep reddish-brown macular dark spots. IR revealed wedge-shaped, wedge-like, or "petaloid-like" dark areas involving the fovea and parafovea. SW-AF examination showed no obvious abnormality in 39 eyes. Weak autofluorescence dark area were consistent with IR in 19 eyes. NIR-AF examination showed spot-like or flaky self-fluorescent dark areas. OCT examination showed strong reflex lesions spreading vertically upward from the retinal pigment epithelium (RPE) layer in the macular area in the acute stage, showing typical "bean seedling" sign. OCTA revealed reduced blood flow density in the deep capillary plexus (DCP) of 50 eyes. En-face OCT displayed lesion areas that corresponded to the dark areas seen in IR. One month after the initial diagnosis, the condition improved in 18 eyes (47.4%, 18/38). Among the 5 eyes with cotton wool spots, regression of these spots was accompanied by loss of nerve fiber layer in 4 eyes. In cases with optic disc edema, the edema subsided. The "bean sprout" sign disappeared in all affected eyes, and the lesions became localized. The ellipsoid zone and/or interdigitation zone in the lesion areas were discontinuous. ConclusionsCOVID-19-related AMN is characterized by distinctive features. IR fundus reveals wedge-shaped, wedge-like, or petaloid dark areas involving the fovea and parafovea. OCT displays strongly reflective lesions with vertical spread above the RPE. OCTA shows reduced blood flow density in the DCP of the retina.
ObjectiveTo systematically review the diagnostic value of optical coherence tomography angiography (OCTA) for primary open-angle glaucoma (POAG). MethodsThe CNKI, WanFang Data, VIP, CBM, PubMed, Embase, Web of Science, and Cochrane Library databases were electronically searched to collect diagnostic test on OCTA for POAG from inception to February 2024. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. Meta-analysis was then performed by using Stata 15.0 software. ResultsA total of 12 diagnostic tests involving 993 subjects were included. Meta-analysis results showed that the sensitivity/specificity of OCTA for diagnosing peripapillary vessel density, retinal vessel density, and optic nerve fiber changes in patients with POAG were 0.77/0.92, 0.56/0.92, and 0.85/0.91, respectively, and the AUC of the SROC curve was 0.94, 0.92 and 0.95, respectively. ConclusionOCTA has high diagnostic accuracy for POAG. Due to the limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.
Objective To compared the changes of macular microvascular architecture in early stage familial exudative vitreoretinopathy (FEVR) patients with inner retinal layer (IRL) persistence and without IRL persistence. MethodsA retrospective clinical study. From 2017 to 2022, 94 patients with stage 1 FEVR with or without IRL residue and 45 age- and sex-matched healthy volunteers with 45 eyes (normal control group) who were confirmed by ophthalmology examination in Hangzhou Hospital of Optometry Affiliated to Wenzhou Medical University and Zhejiang Provincial People's Hospital were included in the study. According to whether there was IRL residue, the patients were divided into IRL group and non-IRL group, with 22 patients (22 eyes) and 72 patients (72 eyes), respectively. Best corrected visual acuity (BCVA) and optical coherence tomography angiography (OCTA) were performed in all eyes. Superficial vessel density (SCP) and deep vessel density (DCP) of whole image, fovea and parafovea, the area and perimeter of fovea avascular area (FAZ), A-circularity index (AI, perimeter/standard circle perimeter with equal area) and vessel density around the 300 μm width of the FAZ (FD), central macular thickness (CMT) on macular 3 mm × 3 mm scan on OCTA were measured. ResultsSCP and DCP of whole image (F=10.774, 4.583) and parafovea (F=10.433, 3.912), CMT (F=171.940) in IRL group and non-IRL group on macular 3 mm × 3 mm scan on OCTA were significantly lower than that in normal persons (P＜0.05). There were significant differences among three groups of the area of FAZ (F=4.315), AI (F=3.413), FD-300 (F=13.592) (P＜0.05). BCVA were worst in IRL group (P＜0.05). ConclusionsBlood flow density decreased in macular area of FEVR patients. CMT is significantly thicker than normal population. The FAZ area of the foveal IRL residual eyes is small and irregular, with worse BCVA and lower macular blood density.
Central serous chorioretinopathy (CSC) is one of the representative pachychoroid spectrum disease. Although fundus fluorescein angiography and indocyanine green angiography can be used as the gold standard for the diagnosis of CSC, they are invasive examinations, which may bring certain risks in clinical application and cannot help us obtain quantitative parameters. Optical coherence tomography angiography (OCTA), as a non-invasive and quantitative examination, is an important imaging tool for understanding the pathogenesis, diagnosis and treatment of CSC. With the advancement of OCTA, the swept-source OCTA has a satisfying scanning depth, a wider scanning range and a higher resolution. The development of OCTA broadens the horizons of the pathogenesis of CSC, promotes the understanding of the pathophysiology of CSC, and sheds new light for its clinical diagnosis and treatment. Based on OCTA, the choroid and retina in eyes with CSC are presented with qualitative and quantitative changes in vascular system. OCTA-guided CSC treatment and the discovery of prognostic markers based on OCTA challenge the application of traditional imaging techniques in CSC. With the continuous improvement and progress of OCTA technology, traditional angiography combined with OCTA will bring great benefits to the diagnosis and treatment of CSC. This review summarizes the quantitative application of OCTA in the pathogenesis, diagnosis and treatment of CSC.
ObjectiveTo observe the changes of macular structure and microvessels in eyes with diabetes macular ischemia (DMI). MethodsA retrospective case study. From January 2023 to July 2023, 23 patients of 31 eyes diagnosed with DMI at Tangshan Ophthalmological Hospital were included in this study. Among them, there were 14 males with 23 eyes; Female cases with 8 eyes. Age were (59.5±4.6) years old. According to the DMI grading standard formulated by the research group for early treatment of diabetes retinopathy, the patients were divided into mild DMI group, moderate DMI group, and severe DMI group, with 8, 12, and 11 eyes respectively. The blood flow density (VD), perfusion area (FA), small vessel VD (SVD), inner retinal capillary plexus VD, FA, and outer retinal, choroidal, and ganglion cell complex (GCC) thickness within 1 mm of the macular fovea in retinal superficial vascular plexus (SVP)were measured using a scanning frequency light source optical coherence tomography instrument. The changes in macular structure and microvasculature in the affected eyes of different degrees of DMI groups were compared and observed. Inter group comparisons were conducted using one-way ANOVA or Kruskal Wallis H-test. Spearman correlation analysis was used to analyze the correlation between DMI severity and GCC, outer retina, choroid thickness, VD, FA and SVP VD, SVD and FA in inner retina. ResultsThe GCC (F=70.670), outer retinal thickness (H=12.393), VD (F=105.506), SVD (H=25.300), FA (F=107.655), and VD (H=24.098) and FA (H=25.300) of the retinal SVP in the mild, moderate, and severe DMI groups were compared, and the differences were statistically significant (P＜0.05). There was no statistically significant difference in choroidal thickness (H=2.441, P＞0.05). Pairwise comparison between groups: VD, SVD, FA of GCC thickness and SVP, and VD of inner retina were statistically significant between severe DMI group and moderate DMI group, and between moderate DMI group and mild DMI group (P＜0.05). The thickness of outer retina was statistically significant between severe DMI group and moderate DMI group (P＜0.05). Inner retinal FA: there were statistically significant differences between severe DMI group, moderate DMI group and mild DMI group (P＜0.05). The correlation analysis results showed that GCC (rs=－0.918), outer retinal thickness (rs=－0.448), and inner retinal VD (rs=－0.894) and FA (rs=－0.918), as well as VD (rs=－0.919), SVD (rs=－0.924), and FA (rs=－0.939) of retinal SVP, were all negatively correlated with the degree of DMI (P＜0.05). There was no correlation between choroidal thickness and degree of DMI (rs=－0.081, P＞0.05). ConclusionThe thickness of GCC, outer retina and choroid, the VD, SVD, and FA of the retinal SVP, the VD and FA of inner retina are all reduced in eyes with different degrees of DMI, while all of them are negatively correlated with the degree of DMI, except for choroid thickness.
Optical coherence tomography angiography (OCTA), as a non-invasive three-dimensional fundus vascular imaging technique, has significant advantages in the diagnosis and follow-up of eye diseases such as diabetic retinopathy and age-related macular degeneration. However, the existence of OCTA image artifacts has seriously affected its clinical application. These artifacts are caused by various factors such as image acquisition, internal characteristics of the eyeball, eye movement and image processing, such as weak signals, blinking, defocusing, bands, tilting, occlusion, exposure, projection, movement and layering, leading to vascular quantization deviation, lesion blurring and image distortion, thereby reducing the accuracy of clinical diagnosis. To address this issue, researchers have proposed a variety of correction strategies, including enhancing signal strength, optimizing equipment, developing algorithms to identify and eliminate shadow artifacts, using hardware or software methods for motion correction, and employing deep learning algorithms for image quality assessment and artifact removal. Constructing a unified and systematic framework for artifact cognition and processing is crucial for enhancing the reliability of OCTA diagnostic results and will drive the level of ophthalmic diagnosis and treatment to a new height.
ObjectiveTo observe the efficacy of optical coherence tomography angiography (OCTA) guided half-dose photodynamic therapy (PDT) in the treatment of acute central serous chorioretinopathy (CSC). MethodsA prospective randomized controlled trial. A total of 72 patients (72 eyes) with acute CSC in Peking University People's Hospital from April 2019 to April 2020 were included in the study. They were randomly divided into OCTA group (OCTA-guided PDT, 31 eyes of 31 patients) and indocyanine green angiography (ICGA) group (ICGA-guided PDT, 33 eyes of 33 patients). All patients underwent best corrected visual acuity (BCVA), fundus color photography, OCTA and ICGA examinations. International standard visual acuity chart was used for BCVA examination, which was converted into logarithm of the minimum angle of resolution (logMAR) visual acuity. In OCTA group, the hyper-reflective area on en face OCTA image at choriocapillaris level was identified as treating area. In ICGA group, the area of choroidal vascular hyperpermeability on ICGA which was related to the leakage on fundus fluorescein angiography (FFA) was identified as treating area. The area corresponding to the treating area on FFA or ICGA was outlined on the color fundus photograph to guide PDT laser spot. The complete subretinal fluid (SRF) resolution, BCVA, central retinal thickness (CRT) at 1, 3, 6 months and SRF recurrent rate at 3, 6 months were observed. Continuous variables between the two groups were compared by t-test or Wilcoxon rank sum test. The χ2 test was used to compare the categorical variables. ResultsAt 1, 3 and 6 months after treatment, the SRF absorption rate in OCTA group and ICGA group was 74.2% (23/31), 63.6% (21/33), 87.1% (27/31) and 84.8% (28/33), 96.8% (30/31), 91.9% (31/33), respectively. OCTA-guided PDT was demonstrated noninferior to ICGA-guided PDT for complete SRF resolution at 1, 3, 6 months [95% confidence interval (CI) －11.9%-33.1%, P=0.402; 95%CI －14.7%-19.3%, P=0.107; 95%CI －6.3%-16.1%, P=0.226]. There was no significant difference in the recurrence rate of SRF between the two groups at 3 and 6 months after treatment (χ2=0.009, 0.047; P=0.925, 0.828). The difference of CRT was statistically significant at 6 months (t=2.017, P=0.047). There was no significant difference in logMAR BCVA at 1, 3 and 6 months after treatment (t=0.529, 0.762, 1.017; P=0.581, 0.403, 0.243). ConclusionsDuring 6 months follow-up, OCTA-guided PDT was demonstrated noninferior to ICGA-guided PDT for the SRF absorption rate in patients with acute CSC.
ObjectiveTo observe changes in peripapillary blood flow before and after combined treatment with anti-vascular endothelial growth factor (VEGF) drugs and Dexamethasone intravitreal implant (DEX) in patients with central retinal vein occlusion (CRVO). MethodsA prospective clinical study. Thirty-three eyes of 33 patients with newly diagnosed non-ischemic CRVO and macular edema (ME) were enrolled from Shanxi Eye Hospital between April 2023 and April 2024. All patients underwent best-corrected visual acuity (BCVA) and swept-source optical coherence tomography angiography (SS-OCTA) examinations. The treatment regimen consisted of three intravitreal injections of ranibizumab and one DEX implant. SS-OCTA was used to scan a 3 mm×3 mm area centered on the optic disc to measure peripapillary retinal nerve fiber layer (RNFL) thickness and blood flow density in the superficial vascular complex (SVC), deep vascular complex (DVC), and radial peripapillary capillaries (RPC). Changes in SVC, DVC, and RPC blood flow density and RNFL thickness were evaluated at 3 and 6 months post-treatment. Shapiro-Wilk test was used to assess normality, and Spearman's rank correlation coefficient was applied for correlation analysis. ResultsCompared with before treatment, the blood flow density changes of SVC and RPC showed a downward trend at 3 and 6 months after treatment. Among them, the difference was statistically significant at 6 months after treatment (Z=−2.592, −2.070, P=0.012, 0.042), while there was no statistically significant difference at 3 months after treatment (P＞0.05). The blood flow density of DVC showed an upward trend at 3 and 6 months after treatment, but the differences were not statistically significant (P＞0.05). The results of the correlation analysis showed that the thickness of RNFL was negatively correlated with the blood flow density of DVC (r=−0.768, P＜0.001). It was positively correlated with the blood flow densities of SVC and RPC (r=0.288, 0.398; P=0.040, 0.004). ConclusionAnti-VEGF drugs combined with DEX treatment can significantly improve the perioptic disc blood flow distribution in eyes with CRVO, manifested as a decrease in blood flow density of SVC and RPC, while a compensatory increase in blood flow of DVC. The thickness variation of RNFL is closely related to the blood flow density of different vascular layers.